The effect of carbon dioxide on the chondriom of some species of higher plants

1962 ◽  
Vol 4 (2) ◽  
pp. 154-159 ◽  
Author(s):  
Marie NadĚŽda KonČalovÁ
Keyword(s):  
Carbon Dioxide ◽  
Higher Plants

Inhibition of δ-Aminolevulinic Acid Synthesis by Glyphosate

Weed Science ◽  
1981 ◽  
Vol 29 (5) ◽  
pp. 571-577 ◽  
Author(s):  
Lynn M. Kitchen ◽  
William W. Witt ◽  
Charles E. Rieck
Keyword(s):  
Carbon Dioxide ◽  
Zea Mays ◽  
Aminolevulinic Acid ◽  
Higher Plants ◽  
Acid Synthesis ◽  
The Other ◽  
Porphyrin Ring ◽  
Fresh Weight ◽  
Ring Compounds ◽  
Site Of Action

The effect of glyphosate [N-(phosphonomethyl) glycine] on barley (Hordeum vulgareL.) and corn (Zea maysL.) shoot δ-aminolevulinic acid (ALA) production was examined by monitoring ALA content in the tissue and measuring incorporation of14C precursors into ALA and chlorophylla. Barley shoot ALA content was significantly decreased by 1 mM glyphosate after 9, 11, and 15 h of illumination. ALA production by treated barley shoots was 30 nmoles•g fresh weight-1•h-1at each interval tested, compared with 75 to 120 nmoles•g fresh weight-1•h-1for the control. In corn shoots, ALA content was reduced 32, 45, and 58% by 0.1, 1.0, and 10.0 mM glyphosate, respectively, after 12 h illumination. Incorporation studies with14C-glutamate,14C-α-ketoglutarate, and14C-glycine into ALA showed a 77, 92, and 91% inhibition, respectively, in barley shoots treated with 1 mM glyphosate. Incorporation of14C-ALA into chlorophyllawas not affected by 1 mM glyphosate. Thus, the site of action of glyphosate may involve two enzyme pathways:one controlling the conversion of α-ketoglutarate to ALA, and the other controlling the condensation of glycine with succinyl CoA to form ALA and carbon dioxide. Inhibition of ALA synthesis blocks synthesis of chlorophyll, as well as all other porphyrin ring compounds found in higher plants. Thus, inhibition of ALA synthesis may be an integral component of the herbicidal mode of action of glyphosate.

The behaviour of plants in various gas mixtures

1971 ◽  
Vol 179 (1056) ◽  
pp. 177-188
Keyword(s):  
Carbon Dioxide ◽  
Gas Exchange ◽  
Partial Pressure ◽  
Higher Plants ◽  
Dry Mass ◽  
Carbon Dioxide Partial Pressure ◽  
Ambient Oxygen ◽  
Leaf Dry Mass ◽  
Rate Of Photosynthesis ◽  
Effect Of Oxygen

The effects of the composition and pressure of the ambient gas mixture on the diffusive gas exchange of leaves, and the effects of carbon dioxide and oxygen on respiration and photosynthesis are described. When photosynthesis is limited by the rate at which carbon dioxide reaches the chloroplasts, the net rate of photosynthesis of many (but not all) plant species depends on the ambient oxygen partial pressure. The effect of oxygen may be principally to stimulate a respiratory process rather than to inhibit carboxylation. However, when photosynthesis is not limited by the carbon dioxide supply, this respiratory process seems to be suppressed. The gas exchange of plant communities responds to the aerial environment in the way expected from measurements on single leaves, but the growth response to a given difference in gas composition is smaller than expected because of adaptation, notably in the ratio of leaf dry mass to leaf area. It is concluded that the growth rate of higher plants in given illumination will be independent of the partial pressure of oxygen and of other gases likely to be used to dilute it, provided that the carbon dioxide partial pressure is so adjusted (probably to not more than 2 mbar (200 Pa)) that the rate of photosynthesis is not limited by the rate of diffusion to the chloroplasts.

scholarly journals The respiration of barley plants I—Methods for the determination of carbohydrates in leaves

1935 ◽  
Vol 117 (806) ◽  
pp. 483-504 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Analytical Methods ◽  
Higher Plants ◽  
Carbon Dioxide Production ◽  
Subsequent Paper ◽  
Oxidative Breakdown ◽  
External Conditions ◽  
Experimental Difficulty

There is much evidence to show that under normal circumstances the respiration of higher plants involves the oxidative breakdown of hexose carbohydrate. During leaf starvation under carefully controlled external conditions, a gradual exhaustion of the carbohydrate substrate is, therefore, one of the important internal changes likely to affect the rate of carbon-dioxide production. The researches to be described here, and in a subsequent paper, were planned in order to test this possibility; an attempt has been made to discover the relation between the con­centration of readily available carbohydrate and the rate of carbon-dioxide production in starving leaves. The chief experimental difficulty involved was that of making accurate determinations of the various hexose sources present in the leaf, and methods whereby this could be done were tested extensively. Since the validity of many of the conclusions reached depends primarily on the accuracy of the analytical methods, it was considered important that an account of these should be included here. It is with this phase of the problem that the present paper is concerned.

Effect of oxygen concentration on the rates of photosynthesis and photorespiration of some higher plants

1973 ◽  
Vol 51 (2) ◽  
pp. 457-464 ◽  
Author(s):  
A. L. D'Aoust ◽  
D. T. Canvin
Keyword(s):  
Carbon Dioxide ◽  
Oxygen Concentration ◽  
Oxygen Tension ◽  
Higher Plants ◽  
Carbon Dioxide Concentration ◽  
Gas Mixture ◽  
Low Carbon ◽  
Leaf Material ◽  
Leaf Chamber ◽  
Effect Of Oxygen

Carbon dioxide gas exchange of leaf material was studied in the light at different oxygen tensions for two CO2 concentrations, using an isotope technique. With bean, radish, and tobacco leaves in the leaf chamber, increasing the oxygen tension resulted in a significant alteration in the 14CO2/CO2 ratio of the gas mixture leaving the leaf chamber as compared to that offered to the leaf material. On estimating the rates of “true’ and apparent photosynthesis it was found that below 5% oxygen concentration the rates were not significantly different. However, increasing the oxygen concentration of the gas mixture resulted in a proportional decrease in the rates of true and of apparent photosynthesis. The increasing oxygen tension also resulted in proportional increases in the CO2 evolution (true photosynthesis minus apparent photosynthesis). The percentage inhibition of apparent photosynthesis was greater at low carbon dioxide concentration, while the inhibition of true photosynthesis was not as sensitive to the carbon dioxide level. The inhibition of apparent photosynthesis was not entirely attributable to the increased photorespiration but was roughly equally divided between an inhibition of true photosynthesis and a stimulation of CO2 evolution in the light.However, with corn leaf material, there was no effect of oxygen concentration on both the rates of true and apparent photosynthesis; also, no large CO2 evolution could be detected as emerging from leaf in the light at any of the oxygen concentrations tested.

scholarly journals Carbon Dioxide Fixation into Oxalacetate in Higher Plants.

1957 ◽  
Vol 32 (6) ◽  
pp. 591-600 ◽  
Author(s):  
Mendel Mazelis ◽  
Birgit Vennesland
Keyword(s):  
Carbon Dioxide ◽  
Higher Plants ◽  
Carbon Dioxide Fixation

Microbial primary production and phototrophy

2018 ◽  
Author(s):  
David L. Kirchman
Keyword(s):  
Carbon Dioxide ◽  
Primary Production ◽  
Microbial Mats ◽  
Higher Plants ◽  
Net Primary Production ◽  
Terrestrial Plants ◽  
Anoxygenic Photosynthesis ◽  
Photosynthetic Organisms ◽  
Anoxic Environments ◽  
Large Numbers

This chapter is focused on the most important process in the biosphere, primary production, the turning of carbon dioxide into organic material by higher plants, algae, and cyanobacteria. Photosynthetic microbes account for roughly 50% of global primary production while the other half is by large, terrestrial plants. After reviewing the basic physiology of photosynthesis, the chapter discusses approaches to measuring gross and net primary production and how these processes affect fluxes of oxygen and carbon dioxide into and out of aquatic ecosystems. It then points out that terrestrial plants have high biomass but relatively low growth, while the opposite is the case for aquatic algae and cyanobacteria. Primary production varies greatly with the seasons in temperate ecosystems, punctuated by the spring bloom when the biomass of one algal type, diatoms, reaches a maximum. Other abundant algal types include coccolithophorids in the oceans and filamentous cyanobacteria in freshwaters. After the bloom, small algae take over and out-compete larger forms for limiting nutrients because of superior uptake kinetics. Abundant types of small algae include two coccoid cyanobacteria, Synechococcus and Prochlorococcus, the latter said to be the most abundant photoautotroph on the planet because of its large numbers in oligotrophic oceans. Other algae, often dinoflagellates, are toxic. Many algae can also graze on other microbes, probably to obtain limiting nitrogen or phosphorus. Still other microbes are mainly heterotrophic but are capable of harvesting light energy. Primary production in oxic environments is carried out by oxygenic photosynthetic organisms, whereas in anoxic environments with sufficient light, it is anaerobic anoxygenic photosynthesis in which oxygen is not produced. Although its contribution to global primary production is small, anoxygenic photosynthesis helps us understand the biophysics and biochemistry of photosynthesis and its evolution on early Earth. These microbes as well as aerobic phototrophic and heterotrophic microbes make up microbial mats. These mats can provide insights into early life on the planet when a type of mat, “stromatolites,” covered vast areas of primordial seas in the Proterozoic.

Sign in / Sign up

Export Citation Format

Share Document